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Although chickens can improve the chemical properties of soil through the deposition of excreta, their effects on soil macrofauna are poorly known. This work assessed the effects of grazing indigenous laying hens on soil macrofauna of two agroecosystems in Portugal: an organic horticultural field and a conventional orchard. At the horticultural field, laying hens were used to control weeds and the results were compared with those of two other weed control treatments: mechanical (rototiller) and thermal (flame weeding). At the orchard, the effects of hens were compared to that of the orchard understory vegetation, as a control. Soil epigeic macrofauna was collected in both locations, and earthworms were only collected in the horticultural field. Relative to the other treatments, grazing in the horticultural field increased the density of earthworms in the medium term (ranging from 150 to 625 earthworms/m2), without harming the density and diversity of epigeic macrofauna. However, at the orchard, the grazed soils presented lower soil epigeic macrofauna diversity, as well as significantly lower density of spiders than the control (4.67 vs 8.67 individuals/sample, respectively). These results suggest that the grazing effects can be affected by several factors, including the type of agroecosystem and farm management. Further research is required to optimize grazing management in different farming systems, considering animal density and grazing duration, thus ensuring the best contributions of chickens to soil fertility.

In this work, the effect of the addition of reduced graphene oxide (rGO) nanoflllers to UHMWPE was investigated. The UHMWPE/rGO nanocomposites were prepared at rGO contents of 0.010, 0.10, 0.25, and 0.50 wt%. The morphological, mechanical, and surface properties of the nanocomposites and the neat UHMWPE were evaluated and related with their tribological behavior. For that, DSC, SEM, contact angle, MO, and profilometry techniques, besides shore D hardness tests, instrumented indentation tests and pin-on-disc sliding wear tests were performed. The results showed that nanocomposites with rGO contents of 0.10 and 0.25 wt% exhibited higher crystallinity degree than the neat UHMWPE, which improved significantly their mechanical and tribological behavior through increases of around 40% in the instrumented hardness and the elastic modulus, and a significant reduction of up to 48% in the coefficient of friction when compared to the neat UHMWPE. Additionally, the presence of rGO decreased the work of adhesion of the nanocomposites/ counterface pairs, resulting in friction and wear mechanisms changes in comparison with the neat polymer. KEYWORDS friction, nanocomposites, reduced graphene oxide, sliding wear, UHMWPE, work of adhesion, 1 | INTRODUCTION Ultra-high molecular weight polyethylene (UHMWPE) has been extensively used in engineering applications that involve wear and friction due to their self-lubricity, lightweight, corrosion resistance, and low coefficient [...]

The 2022 Economic Report of the President devotes a whole chapter to the role of monopsony, monopoly, and discrimination as barriers to economic equality. That monopsony power --market power held [...]

Water is crucial for enduring horticultural productivity, but high water-use requirements and declining water supplies with the changing climate challenge economic viability, environmental sustainability, and social justice. While the scholarly literature pertaining to water management in horticulture abounds, knowledge of practices and technologies that optimize water use is scarce. Here, we review the scientific literature relating to water requirements for horticulture crops, impacts on water resources, and opportunities for improving water- and transpiration-use efficiency. We find that water requirements of horticultural crops vary widely, depending on crop type, development stage, and agroecological region, but investigations hitherto have primarily been superficial. Expansion of the horticulture sector has depleted and polluted water resources via overextraction and agrochemical contamination, but the extent and significance of such issues are not well quantified. We contend that innovative management practices and irrigation technologies can improve tactical water management and mitigate environmental impacts. Nature-based solutions in horticulture—mulching, organic amendments, hydrogels, and the like—alleviate irrigation needs, but information relating to their effectiveness across production systems and agroecological regions is limited. Novel and recycled water sources (e.g., treated wastewater, desalination) would seem promising avenues for reducing dependence on natural water resources, but such sources have detrimental environmental and human health trade-offs if not well managed. Irrigation practices including partial root-zone drying and regulated deficit irrigation evoke remarkable improvements in water use efficiency, but require significant experience for efficient implementation. More advanced applications, including IoT and AI (e.g., sensors, big data, data analytics, digital twins), have demonstrable potential in supporting smart irrigation (focused on scheduling) and precision irrigation (improving spatial distribution). While adoption of technologies and practices that improve sustainability is increasing, their application within the horticultural industry as a whole remains in its infancy. Further research, development, and extension is called for to enable successful adaptation to climate change, sustainably intensify food security, and align with other Sustainable Development Goals. [ABSTRACT FROM AUTHOR]